I don’t really understand your question. On my Mac, choosing Icon Only for the toolbar does not hide the search field. As in other Mac applications, choosing Text Only for the toolbar does hide the search field, as does removing it from the toolbar. Are you expecting to change the toolbar to Icon mode when you press Command-Option-F?
Right now you have to change to Icon mode to see the search field. Perhaps I can change it so that if you press Command-Option-F in Text mode it will automatically switch to icon mode.